Update Ark documentation to 16.08

man page
  proofread, bump date + releaseinfo, add "See Also" with info about more qt + kf5 options

handbook
  proofread, bump date + releaseinfo
  add features integrity test, compression and multi-volume
  update / add screenshot

content + pngs from https://rthomsen6.wordpress.com/2016/08/01/ark-improvements-in-16-08/
REVIEW:128645